I've been pretty bored this weekend.. So after i got sick of scrambling my Rubiks cube and solving it and then seeing what pattern i could create umpteen times....
http://i280.photobucket.com/albums/k...1020081651.jpg
I decided it was time to go machine something.. Anything! haha.
The best choice i came up with was lightening my intermediate shaft.
I chucked it in the lathe and went to town on it..
The casting, although quite good, with virtually no mismatch was eccentric but about 1.5mm! Bloody terrible.
http://i280.photobucket.com/albums/k...1020081652.jpg
http://i280.photobucket.com/albums/k...1020081653.jpg
The shaft, between the 2 journals basically tapers from one end to the other. Luckily the smaller end is pretty close to spot on concentric, and then it obviously gets worse as if moves along to the other end.
What i have done is turned it down to 18.0mm from one end to the other, with 9mm radii in the corners to ensure there is no weak point. 18mm was just enough to clean up the smaller end.
http://i280.photobucket.com/albums/k...1020081654.jpg
http://i280.photobucket.com/albums/k...1020081655.jpg
http://i280.photobucket.com/albums/k...1020081656.jpg
http://i280.photobucket.com/albums/k...1020081657.jpg
Obviously, the shaft would still not be perfectly balanced, but it would be more than close enough. Because it runs at half speed, at maximum engine speed, which in my case will hopefully be about 9000rpm or a little less, the intermediate shaft will be doings no more than 4500rpm ever. Also, there is much less rotating mass aswell as a very small diameter. So therefore, balancing is much less critical.
If anyone else is interested, i can provide these types of services for them, too. (Hows that for blowing my own trumpet.. :biggrin: )